CBS Industry Co Ltd show in the 2015 ZAK doors and windows expo. We present the latest new model of WMH-318 uPVC windows 3-head welding machine, which have innovative design, the max. welding height is 180mm, recangle linear guideway for the clamps. Linear guideway for the welding head. It's a 3-head welding machine, but have 4 welding position, that means it can work like a 4-head welding machine.